When the alteration of the Second Part (that is, the difference between Part IV and Part II) is sufficiently radical to suggest the presence of a virtually new Part, the design is called the Five-part Song-form.

The possible repetition of the First Part, it will be inferred, does not affect this distinction in the least; it hinges solely upon the treatment of the reproduction of _Part Two_.
For illustration: [Illustration: Diagram of Parts.] The Five-Part form is illustrated in the 14th Song Without Words;--( first, number the measures; observe that the two endings of Part I are to be counted as the _same measure_, and not separately; they are both measure 8):--Part I extends to the double-bar, and is repeated literally, only excepting the _rhythmic_ modification of the final measure; Part II extends from measure 9 to 23; Part III, measures 24-35; Part IV, measures 36-47; Part V, measures 48-60; coda to the end.

The comparison of Part IV with Part II discloses both agreement and diversity; they are, obviously, _practically the same Part_, but differ in key, in form, and in extent.

The comparison of Parts I, III, and V reveals a similar condition, though the agreement here is much closer, and each confirms the leading statement.
A more characteristic example will be found in the familiar F major _Nachtstueck_ of Schumann, op.

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